Techniques for supporting user equipment paging in an enterprise fabric

ABSTRACT

In one example, a control plane entity obtains an indication that a User Equipment (UE) has entered an idle mode. The control plane entity sets a routing locator corresponding to the UE to cause the control plane entity to trigger a paging request toward the UE to prompt the UE to transition from the idle mode when a first network node obtains a downlink packet destined for the UE. The control plane entity obtains a notification that the first network node has obtained the downlink packet and initiates the paging request toward the UE. The control plane entity updates the routing locator corresponding to the UE to cause the first network node to transmit further downlink packets destined for the UE toward a second network node configured to handle traffic on behalf of the UE.

TECHNICAL FIELD

The present disclosure relates to computer networking.

BACKGROUND

A User Equipment (UE) in communication with a network can go into idlemode in order to save battery. In idle mode, only the control channel isup, and the UE does not send or receive any data to or from the network.Paging is a mechanism defined in 3rd Generation Partnership Project(3GPP) architecture in which the network wakes up the UE from idle modeupon detecting downlink traffic destined for the UE. Upon receiving apaging request from the network, the UE may exit the idle mode, andthereby begin sending and/or receiving data.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a system configured to support User Equipment (UE)paging, according to an example embodiment.

FIGS. 2A and 2B collectively illustrate a flow diagram of a method forsupporting UE paging, according to an example embodiment.

FIGS. 3A-3D illustrate graphical representations of UE mobility from aforwarding perspective when the UE transitions between an idle mode(e.g., Radio Resource Control (RRC) idle mode) and a connected mode(e.g., RRC connected mode), according to an example embodiment.

FIG. 4 illustrates a block diagram of a computing device configured tosupport UE paging, according to an example embodiment.

FIG. 5 illustrates a flowchart of method for supporting UE paging,according to an example embodiment.

DESCRIPTION OF EXAMPLE EMBODIMENTS Overview

In one example embodiment, a control plane entity of a network fabricobtains an indication that a User Equipment (UE) connected to thenetwork fabric has entered an idle mode. In response to obtaining theindication that the UE has entered the idle mode, the control planeentity sets a routing locator corresponding to the UE to cause thecontrol plane entity to trigger a paging request toward the UE to promptthe UE to transition from the idle mode when a first network node of thenetwork fabric obtains a downlink packet destined for the UE. Thecontrol plane entity obtains a notification that the first network nodehas obtained the downlink packet. In response to obtaining thenotification that the first network node has obtained the downlinkpacket, the control plane entity initiates the paging request toward theUE. Upon obtaining an indication that the UE has transitioned from theidle mode, the control plane entity updates the routing locatorcorresponding to the UE to cause the first network node to transmitfurther downlink packets destined for the UE toward a second networknode of the network fabric configured to handle traffic on behalf of theUE.

Example Embodiments

FIG. 1 illustrates an example system 100 configured to support UserEquipment (UE) paging. System 100 includes UE 105, tracking area 110,network fabric 115 and Data Network (DN) 120. Tracking area 110 includesAccess Points (APs) 125(1)-125(3), which provide network access coverageto respective coverage areas 130(1)-130(3). Network fabric 115 includesa Cellular Termination Function (CTF) 135, Wireless Local Area Network(LAN) Controller (WLC) 140, Map-Server (MS) 145, and any combination of:an Authentication, Authorization, and Accounting (AAA) server/function,a Network Policy Function (NPF), and/or a 3rd Generation PartnershipProject (3GPP) Home Subscriber Server (HSS) 150 (referred to herein asAAA/NPF/HSS 150). Network fabric 115 further includes switch 155,network nodes (e.g., routers) 160(1)-160(4), and border node 165.

UE 105 may be associated with any suitable device configured to initiatea flow in system 100. For example, UE 105 may include a computer, avehicle and/or any other transportation-related device having electronicdevices configured thereon, an automation device, an enterprise device,an appliance, an Internet of Things (IoT) device, a Personal DigitalAssistant (PDA), a laptop or electronic notebook, a cellular telephone,a smartphone, a tablet, an Internet Protocol (IP) phone, and/or anyother device and/or combination of devices, components, elements, and/orobjects capable of initiating voice, audio, video, media, or dataexchanges within system 100. UE 105 may also include any suitableinterface to a human user such as a microphone, a display, a keyboard,or other terminal equipment. UE 105 may also be any device that seeks toinitiate a communication on behalf of another entity or element such asa program, a database, or any other component, device, element, orobject capable of initiating an exchange within system 100. UE 105 maybe configured with appropriate hardware (e.g., processor(s), memoryelement(s), antennas and/or antenna arrays, baseband processors(modems), and/or the like), software, logic, and/or the like tofacilitate respective over-the-air (air) interfaces foraccessing/connecting to APs 125(1)-125(3). It will be appreciated thatany number of UEs may be present in system 100.

One or more of APs 125(1)-125(3) may be cellular APs that terminate acellular (e.g., 4G Long-Term Evolution (LTE) or 5G New Radio (NR)) airinterface and may be configured with appropriate hardware (e.g.,processor(s), memory element(s), antennas and/or antenna arrays,baseband processors (modems), and/or the like), software, logic, and/orthe like to provide over-the-air coverage for a private cellular accessnetwork (e.g., private 4G LTE, private 5G NR, private Citizens BroadbandRadio Service (CBRS), etc.). By ‘private’ it is meant that a privatecellular access network provides network connectivity/services toclients (e.g., UE 105) served by a network operator and/or serviceprovider of the private cellular access network, such as an enterprise.In one example, a private cellular access network may be considered tobe a network that may be implemented to serve enterprise purposes (e.g.,business purposes, government purposes, educational purposes, etc.) forenterprise clients (e.g., enterprise users/devices/etc.) in which theprivate cellular access network may be operated by any combination oftraditional mobile network operators/service providers, enterprisesnetwork operators/service providers, and/or third party networkoperators/service providers (e.g., neutral host networkoperators/service providers, cloud service providers, etc.). In variousembodiments, APs 125(1)-125(3) may be implemented as any combination ofan evolved Node B (eNB) to facilitate 4G LTE air accesses, a nextgeneration Node B (gNB) to facilitate 5G NR air accesses, a nextgeneration (nG) radio to facilitate any next generation air accesses, aCBRS Device (CBSD) to facilitate CBRS accesses, and/or the like nowknown or hereafter developed.

One or more of APs 125(1)-125(3) may be Wireless LAN (WLAN) APsconfigured with appropriate hardware (e.g., processor(s), memoryelement(s), antennas and/or antenna arrays, baseband processors(modems), and/or the like), software, logic, and/or the like to provideover-the-air coverage for a WLAN access network (e.g., Wi-Fi®). Invarious embodiments, one or more of APs 125(1)-125(3) may be implementedas Wi-Fi APs and/or the like. Although illustrated as separate APs, insome embodiments one or more of APs 125(1)-125(3) may be combined APs toprovide any combination of cellular and WLAN accesses.

Network fabric 115 may be associated with a private network, such as asoftware-defined access fabric configured specifically for use by usersassociated with an enterprise. In one example, the user of UE 105 is anemployee of the enterprise associated with network fabric 115.

CTF 135 may be a control plane entity that provides or is responsiblefor any combination of cellular-based access authentication services,authorization services, mobility management control, session managementservices with various functions being supported on a per-session basis,selection and control of user plane entities (e.g., per-session), ifapplicable, and/or the like. In various embodiments, CTF 135 may beimplemented with functionality as may be inherited from any combinationof a 4G LTE Mobility Management Entity (MME); a Serving Gateway (SGW),and/or a Packet Data Network (PDN) Gateway (PGW); a 5G Access andMobility Management Function (AMF) and/or Session Management Function(SMF); and/or the like now known or hereafter developed. In one example,CTF 135 may terminate the S1-MME interface (in the 4G case) or the N1interface (in the 5G case) from one or more of APs 125(1)-125(3) (e.g.,one or more eNBs/gNBs).

WLC 140 may be a control plane entity that provides or is responsiblefor WLAN functions such as WLAN-based access authentication services,authorization services, intrusion prevention, Radio Frequency (RF)management, and/or the like to facilitate UE 105 connectivity via one ormore of APs 125(1)-125(3). In some implementations, WLC 140 may beconfigured as an evolved WLC (eWLC). CTF 135 and WLC 140 may beconfigured as separate entities or as combined or converged as a singlemulti-access termination function configured to provide operations,functions, etc. for multiple accesses that may be provided via APs125(1)-125(3).

MS 145 is a control plane entity (e.g., a Locator Identity (ID)Separation Protocol (LISP) function) that represents a distributedmapping database and service that accepts registration information forclients and/or other endpoint users/devices, etc. (e.g., UE 105), andstores mappings between numbering or name space constructs. LISP is acontrol plane protocol that may facilitate IP mobility for system 100.Although embodiments herein provide example details associated with aLISP implementation, other control plane protocols may be implementedfor system 100 including, but not limited to, Proxy Mobile IP version 6(PMIPv6), Identifier Locator Addressing (ILA), etc.

A LISP implementation may utilize various constructs including RoutingLocators (RLOCs) that may be associated with edge and border switches(e.g., switch 155) and Endpoint Identifiers (EIDs) that may beassociated with/identify clients or other endpoints (e.g., UE 105) inorder to facilitate mobility for network fabric 115. An RLOC is an IPaddress associated with an element in which the nomenclature‘RLOC=element’ may generally represent an RLOC set to the IP address ofthe element. IP addresses as discussed for embodiments described hereinmay be implemented as IP version 4 (IPv4) and/or IPv6 addresses. Othervariations for setting an RLOC may be envisioned using, for example,Type-Length-Value (TLV) expressions, or the like.

For the LISP implementation of system 100, MS 145 may store mappings,generally known as EID-to-RLOC mappings, between RLOCs for fabricswitches/functions/etc. (e.g., switch 155) and EIDs for clients (e.g.,UE 105) for which traffic is handled or otherwise associated with theswitches/functions/etc. MS 145 may associate EIDs with any combinationof IP and/or Media Access Control (MAC) addresses for a client fordifferent EID-to-RLOC mappings that may be maintained/managed withinnetwork fabric 115. MS 145 may also communicate EID-to-RLOC mappinginformation to various elements of network fabric (e.g., WLC 140,AAA/NPF/HSS 150 etc.). MS 145 may include map resolver functionalitysuch as obtaining map request messages and processing/forwarding thosemessages for MS 145. Such information may be stored in the map-cache ofthe elements to facilitate routing via network fabric 115.

AAA/NPF/HSS 150 may provide/be responsible for any combination of:providing authentication, authorization, and accounting functions forclients (e.g., UE 105) that may be present in system 100; managingsubscription/policy information for one or more clients that may bepresent in system 100 (e.g., access profile information, as discussedbelow, among other subscription/policy information); maintainingper-client session information for various accesses to which each clientis connected; combinations thereof; and/or the like. In variousembodiments, AAA/NPF/HSS 150 may be implemented as any combination ofstandalone and/or combined elements (e.g., separate AAA, NPF, and HSSelements; a combined AAA/HSS element without an NPF element; an AAAelement and an NPF element without an HSS element; etc.) in order tofacilitate authentication, authorization, and accounting operations(referred to herein as ‘AAA-based’ operations) as well as policy-basedoperations for network fabric 115.

Generally, authentication refers to the process where an entity'sidentity is authenticated, typically by providing evidence that it holdsa specific digital identity such as an identifier/identity andcorresponding credentials/authentication attributes/etc. Generally,authorization can be used to determine whether a particular entity isauthorized to perform a given activity, typically inherited fromauthentication when logging on to an application or service. In variousinstances, authorization may be determined based on a range ofrestrictions, for example time-of-day restrictions, or physical locationrestrictions, or restrictions against multiple accesses by the sameentity or user/device. Generally, accounting refers to the tracking ofnetwork resource consumption by users/devices for the purpose ofcapacity and trend analysis, cost allocation, billing, etc. It will beappreciated that AAA/NPF/HSS 150 may include cellular authentication andWLAN authentication functionality distributed across one or moreservers.

In various embodiments, AAA/NPF/HSS 150 may be configured with or obtain(e.g., from an external database/service/etc.) per-client access profileinformation that may include, but not be limited to, client (e.g.,user/device) identity information, authentication type attributes (e.g.,authentication type, sub-type, etc.), authentication attributes (e.g.,credentials, passwords, keys, etc.), combinations thereof, and/or thelike. Additionally, AAA/NPF/HSS 150 may be configured with or obtain(e.g., from an external database/service/etc.) per-clientsubscription/policy information that may include, but not be limited to,service quality information such as Quality of Service (QoS)information, QoS Class Identifier (QCI), Guaranteed Bit Rate (GBR),Maximum Bit Rate (MBR), Aggregate Maximum Bit Rate (AMBR), Allocationand Retention Priority (ARP), packet delay information, packet lossinformation, combinations thereof, and/or the like for one or moreclient sessions. In various embodiments, subscription/policy informationmay also include a 3GPP service name such as AP Name (APN) information(for 4G networks), Data Network Name (DNN) information (for 5Gnetworks), combinations thereof, and/or the like for one or more clientsessions.

In various embodiments, AAA/NPF/HSS 150 may be configured with one ormore databases/repositories/etc. and/or may interface with one or moreexternal databases/repositories/etc. in order to obtain and/or beconfigured with access profile information, subscription/policyinformation, etc. for clients. Such internal/externaldatabases/repositories/etc. may include any combination of enterprisedatabases, repositories, and/or the like for one or more clients thatmay be allowed to connect to accesses with which network fabric 115 mayinterface. In various embodiments, AAA/NPF/HSS 150 may be implemented asan AAA server, an enterprise policy server/manager, a 3GPP HSS,combinations thereof, and/or the like.

AAA/NPF/HSS 150 may be capable of interfacing/communicating with otherelements of system 100 (e.g., CTF 135 and WLC 140) via any combinationof Remote Authentication Dial-In User Service (RADIUS) protocolmechanisms (e.g., messaging, signaling, etc.), DIAMETER protocol, 3GPPSha interface mechanisms, Sha-based interface mechanisms (e.g., forarchitectures that may involve interfaces based on, but not strictlyadhering, to 3GPP defined Sha interface mechanisms), ApplicationProgramming Interface (API) mechanisms (e.g., for messaging, signaling,etc. that may be defined by an enterprise, 3rd-party, application,etc.), fabric-defined interfaces (e.g., as may be defined by anenterprise), combinations thereof, and/or the like.

Switch 155 and network nodes 160(1)-160(4) may transmit user planepackets between APs 125(1) and DN 120. In particular, switch 155 may beany suitable network node configured to obtain/provide networkcommunications (e.g., packets) from/to APs 125(1)-125(3), and networknodes 160(1)-160(4) may be any suitable network node configured totransmit network communications between switch 155 and border node 165,and border node 165 may be any suitable network node associated with DN120 configured to obtain/provide network communications from/to DN 120.Border node 165 may be an edge router for network fabric 115. In oneexample, switch 155 and/or border node 165 are IP forwarding elementsthat support the LISP ingress/egress Tunnel Router (xTR) functions.Switch 155 may also be referred to interchangeably as a “fabric edgenode” and border node 165 may also be referred to interchangeably as a“fabric border node.” In one example, network nodes 160(1)-160(4) may beunderlay network elements unaware of LISP operations.

In various embodiments, DN 120 may be any combination of the Internet,an Internet Protocol (IP) Multimedia Subsystem (IMS), Ethernet network,Ethernet switching system(s), and/or the like. DN 120 may facilitateuser plane (e.g., user data/data transfer) connectivity for per-accessUE 105 sessions. For example, UE 105 may access various services,applications, etc. from DN 120.

Although various interconnections/interfaces among various elements ofnetwork fabric 115 are illustrated in FIG. 1 (e.g., among control planeentities such as CTF 135, WLC 140, MS 145, and AAA/NPF/HSS 150, and/oramong user plane entities such as switch 155, network nodes160(1)-160(4), and border node 165) it is to be understood that anyelements of network fabric 115 may be interconnected and/or interfaceusing any wired and/or wireless connections to facilitatecommunications, operations, etc. among the elements as discussed fortechniques described herein.

In one example, UE 105 is initially located in coverage area 130(1) andis connected with network fabric 115 via AP 125(1). At some point, UE105 enters an idle mode in which no data can be sent (or received) to(or from) UE 105. Typically, upon receiving a notification that a UEentered idle mode, an MME would trigger a Release Access Bearer requestover an S11 interface towards a SGW. Furthermore, a PGW would typicallyreceive a downlink packet destined for the UE, and then send a triggerto the MME/SGW to cause the MME/SGW to send an S1AP paging message toone or more eNBs. The MME would forward the paging message to eNBswithin the relevant tracking area. For example, the MME might page thelast known location of the UE (before the UE entered idle mode), and ifthere is no response, expand the paging area (e.g., by sending thepaging request to more eNBs). Upon receiving the paging request, the UEwould establish a radio connection with the eNB to establish S1-App andS1-U connections with the MME and SGW.

System 100 integrates the 3GPP control plane with a network fabric baseduser plane (e.g., a software-defined access fabric) to provide privatecellular and/or WLAN services in the enterprise architecture context. Insystem 100, there is no PGW, SGW, or S11 interface, and, as such, system100 cannot ensure that the idle state is reflected in the fabric userplane using conventional approaches. Therefore, standard approaches arenot effective for providing a paging mechanism to wake up UE 105 fromidle mode in system 100.

Accordingly, paging logic 170 may be provided in CTF 135 to enablehandling/processing of idle mode and paging messages in system 100 andother similar systems that enable private cellular and/or WLANenterprise networks. In one example, CTF 135 obtains an indication thatUE 105 has entered an idle mode. In response to obtaining the indicationthat UE 105 has entered the idle mode, CTF 135 provides instructions tocause CTF 135 to be notified when border node 165 obtains, from DN 120,a downlink packet destined for UE 105. Some time later, CTF 135 obtainsa notification that border node 165 has obtained the downlink packet,and, in response to obtaining the notification that border node 165 hasobtained the downlink packet, causes a paging request to be provided toUE 105 to prompt UE 105 to exit the idle mode. CTF 135 may obtain anindication that UE 105 has exited the idle mode and provide instructionsto cause border node 165 to transmit further downlink packets destinedfor UE 105 toward switch 155.

A “correspondent node” may be a network node that originates/providesthe downlink packet toward UE 105. In the aforementioned example, thecorrespondent node is in DN 120 (i.e., outside the domain of networkfabric 115), and therefore the downlink packet hits border node 165.However, the correspondent node may also/alternatively be another UEthat is also part of the domain of network fabric 115. In that case, thedownlink packet may enter via another network node, such as an edgeswitch (e.g., switch 155). It will be appreciated that techniquesdescribed herein may apply to switch 155, border node 165, or any othersuitable network node that supports the LISP xTR functions. Inparticular, the paging trigger may occur at the originating point of thefabric tunnel, or the fabric node closer to the correspondent node.

With continuing reference to FIG. 1, FIGS. 2A and 2B collectivelyillustrate a flow diagram of a method 200 for supporting UE paging. At202, AP 125(1) registers with CTF 135 and CTF 135 learns the RLOC for AP125(1). APs 125(2) and 125(3) may also register with CTF 135, and thusCTF 135 may learn the RLOCs for all APs 125(1)-125(3). Although switch155 is illustrated in FIG. 1 as the RLOC for APs 125(1)-125(3), it willbe appreciated that AP 125(1) may have associated therewith a firstnetwork node corresponding to a first RLOC, AP 125(2) may haveassociated therewith a second network node corresponding to a secondRLOC, and AP 125(3) may have associated therewith a third network nodecorresponding to a third RLOC.

At 204, a Virtual Extensible Local Area Network (VXLAN) access tunnel isestablished between AP 125(1) and switch 155. At 206, UE 105 enters anactive mode and may send/receive data packets to/from DN 120 (via AP125(1) and network fabric 115). At 208, AP 125(1) establishes a defaultbearer for UE 105. At 210, MS 145 saves/stores the EID and Media AccessControl (MAC) address for UE 105 and sets the RLOC corresponding to theEID to switch 155. At 212, CTF 135 establishes the default bearer for UE105.

At 214, UE 105 enters an idle mode. AP 125(1) may determine that UE 105has entered the idle mode in response to the expiration of an idle timerduring which no communications were sent to or received from UE 105. Inresponse to the expiration of the idle timer, at 216 CTF 135 obtains anindication that UE 105 has entered the idle mode. More specifically, CTF135 obtains, from AP 125(1), a context release request for UE 105 due toinactivity of UE 105. The context release request may specify the S1APID assigned by AP 125(1) to UE 105, the International Mobile SubscriberID (IMSI) of UE 105, and the Tracking Area ID (TAI) of UE 105. At 218,CTF 135 provides, to AP 125(1), a context release message prompting AP125(1) to release those radio resources reserved for UE 105. At 220, CTF135 obtains, from AP 125(1), a confirmation of context release for UE105.

At 222, CTF 135 provides instructions to cause CTF 135 to be notifiedwhen border node 165 (or any suitable data plane xTR node attempting tolocate the RLOC for UE 105) obtains, from DN 120, a downlink packetdestined for UE 105. In this example, CTF 135 provides instructions toprovide a trigger to CTF 135 to notify CTF 135 when there is a downlinkpacket that needs to be delivered to UE 105. There are many possibleapproaches for providing this trigger. In the example of FIG. 2, theapproach is to provide the trigger by directly forwarding the downlinkpacket to CTF 135. In this case CTF 135 is updated as the RLOCcorresponding to UE 105, the downlink packet is delivered to CTF 135,and the downlink packet itself serves as the trigger to CTF 135 forinitiating the paging process.

In other approaches (discussed below), a network node (e.g., switch 155or border node 165) is updated as the RLOC corresponding to UE 105, andthe network node may provide a control plane message to CTF 135 (orcause a control plane message to be provided to CTF 135). One approachmay involve sending a control plane message to CTF 135 to prompt CTF 135to initiate the paging process. Another approach may involve sending acontrol plane message to MS 145, which triggers MS 145 to send a mapnotify message to CTF 135 to prompt CTF 135 to initiate the pagingprocess. In these other approaches, the network node may buffer or dropthe downlink packet.

In the example of FIG. 2, CTF 135 initiates a map register function inthe form of a message to MS 145 specifying CTF 135 as the new RLOC of UE105. This causes a downlink IP packet destined for UE 105 to beforwarded to CTF 135 in order to prompt CTF 135 to initiate pagingprocedures. CTF 135 thus replaces switch 155 as the RLOC of UE 105.Switch 155 should not remain as the RLOC of UE 105 when UE 105 is in theidle mode state because UE 105 may switch locations while in idle modeand move to an AP associated with a different network node. In otherwords, switch 155 may no longer be the appropriate network node toreceive downlink packets on behalf of UE 105, because UE 105 may bereachable through a different network node when UE 105 returns to activemode. Switching the RLOC of UE 105 to CTF 135 may account for thepossibility that UE 105 has moved to another AP/network node.

At 224, MS 145 provides, to border node 165, an unsolicited Publicationspecifying the Layer 3 (L3) VXLAN ID (VNID) of the IP address of UE 105,and indicating that CTF 135 is the new RLOC for UE 105. In LISPterminology, a VNID is referred to as a LISP Instance-ID (IID).Typically, a LISP IID is rendered into a VXLAN VNID in data planeelements (e.g., xTRs) for encapsulation. Thus, for variousexamples/discussions provided herein, it is to be understood that a VNIDmay also refer to a LISP

In one example, the Publication may include the EID of UE 105 and theRLOC of CTF 135. Removing the RLOC associated with the EID of UE 105 maycause the idle state to be reflected in the fabric user plane, therebyenabling interworking between the 3GPP control plane elements and thefabric user plane. In one sense a mobility event of UE 105 is activatedas a response to the idle timeout event, bringing CTF 135 into the pathfor downlink traffic destined for UE 105 (e.g., for a transient periodof time while UE 105 is being paged). CTF 135 may thus detect anydownlink data destined for UE 105. MS 145 may provide similarindications to any entities that have asked to receive updates regardingthe mapping for the EID of UE 105 (e.g., including the xTR to which UE105 was previously logically attached). There may be xTRs in networkfabric 115 that have a map-cache entry for the EID of UE 105 but havenot asked to be notified for mapping updates for that EID, but if thosexTRs send data traffic to the previous xTR using a stale map-cacheentry, the previous xTR may redirect the data traffic to CTF 135 andsend a data-triggered Solicit-Map-Request (SMR) back to the xTRoriginating the traffic to notify that xTR that the xTR should updatethe xTR map-cache for that entry.

At 226, border node 165 obtains a downlink packet destined for UE 105from DN 120. The map entry at border node 165 for the EID of UE 105indicates that CTF 135 is the corresponding RLOC, prompting border node165 to forward the packet to CTF 135. Alternatively, border node 165 mayprovide a control plane message to CTF 135 indicating that CTF 135should initiate paging to UE 105. At 228, CTF 135 obtains a notificationthat border node 165 has obtained the downlink packet. In this example,the notification that border node 165 has obtained the downlink packetis the downlink packet itself. For example, CTF 135 may obtain thedownlink packet through a VXLAN fabric tunnel from border node 165 andconclude that border node 165 has obtained the downlink packet. In oneexample, CTF 135 may buffer the downlink packet and later forward thedownlink packet when UE 105 enters the connected mode with MS 145reflecting a registered RLOC for the EID of UE 105.

Upon receiving the downlink IP packet indicating a destination thatmatches the IP address of UE 105, CTF 135 starts a paging timer for UE105 at 230. At 232, CTF 135 causes a paging request to be provided to UE105 to prompt UE 105 to exit the idle mode. In this example, CTF 135provides a paging request for UE 105 to AP 125(1). The paging requestmay include the IMSI of UE 105 and the relevant TAI. CTF 135 mayalso/alternatively provide the paging request to other APs (e.g., APs125(2) and 125(3)) to account for the possibility that UE 105 movedlocations while in idle mode. CTF 135 may provide paging requests to oneor more of APs 125(1)-125(3) according to any suitable process (e.g., inany suitable order). For example, CTF 135 may first send a pagingrequest to AP 125(1), and if it is determined that UE 105 is notcommunicable via AP 125(1), may then send paging requests to APs 125(2)and/or 125(3). APs 125(1)-125(3) need not necessarily be in the sametracking area.

At 234, AP 125(1) provides the paging request to UE 105. At 236, AP125(1) provides a Radio Resource Control (RRC) paging message. At 238,UE 105 provides an RRC connection request to AP 125(1). At 240, AP125(1) provides an RRC connection setup message to UE 105. At 242, UE105 provides, to AP 125(1), an indication that the RRC connection setupis complete. UE 105 may also provide an attach request that specifies aGlobally Unique Temporary Identity (GUTI) or IMSI of UE 105, an attachtype, and a network access server key set. At 244, CTF 135 obtains anindication that UE 105 has exited idle mode in the form of an attachrequest from AP 125(1). The attach request may specify the GUTI or IMSIof UE 105 and the attach type. At 246, CTF 135 provides, to AAA/NPF/HSS150, an authentication information request including the IMSI, PublicLand Mobile Network (PLMN) ID, and TAI. At 248, AAA/NPF/HSS 150validates the PLMN ID and TAI. At 250, CTF 135 obtains an authenticationinformation answer (e.g., an authentication vector) from AAA/NPF/HSS150. At 252, UE 105 is authenticated.

At 254, CTF 135 provides an update location request to AAA/NPF/HSS 150.The update location request may include the IMSI and PLMN ID. At 256,CTF 135 obtains an update location answer from AAA/NPF/HSS 150. Theupdate location answer may include the relevant IMSI, Mobile StationInternational Subscriber Directory Number (MSISDN), APN, and QCI. At258, CTF 135 provides an attach accept message to AP 125(1). The attachaccept message may include the IP address of UE 105 and an uplink TunnelEndpoint ID (TED)/Generic Routing Encapsulation (GRE) key for UE 105. At260, AP 125(1) provides a Non-Access Stratum (NAS) attach accept messageto UE 105 and, at 262, obtains an attach complete message from UE 105.At 264, CTF 135 obtains an attach complete message from AP 125(1). Theattach complete message may include the uplink TEID/GRE key for UE 105.

At 266, CTF 135 provides instructions to cause border node 165 totransmit further downlink packets destined for UE 105 toward switch 155.More specifically, CTF 135 initiates a map register function in the formof a message to MS 145 specifying switch 155 as the new RLOC of UE 105.This causes any downlink IP packets destined for UE 105 to be forwardedto switch 155 (and then to UE 105). Switch 155 thus replaces CTF 135 asthe RLOC of UE 105. At 268, MS 145 provides, to border node 165, anunsolicited Publication specifying the L3 VNID of the IP address of UE105, and indicating that switch 155 is the new RLOC for UE 105. MS 145may provide a similar indication to other xTR nodes. Thus, the map entryand cache at various xTR nodes may be updated to remove CTF 135 from thepath of the user plane traffic. Network fabric 115 may now forward thedownlink traffic to switch 155. At 270, a data plane is establishedbetween UE 105 and AP 125(1). In a further example, CTF 135 may send thebuffered downlink packet to UE 105 in order to prevent UE 105 frommissing the initial downlink packet.

FIGS. 3A and 3B illustrate example graphical representations 300A and300B of UE mobility from a forwarding perspective when UE 105transitions between an idle mode (e.g., RRC idle mode) and a connectedmode (e.g., RRC connected mode) according to method 200. Graphicalrepresentation 300A illustrates a fabric mobility event in which UE 105enters idle mode. Here, network fabric 115 hides (in a forwarding sense,as illustrated by dashed line 305) UE 105 behind CTF 135 when thenetwork detects that the idle timer has expired and the reachabilitystate of UE 105 is unknown. To accomplish this, network fabric 115registers CTF 135 as the RLOC for UE 105 upon detecting the expiry ofthe idle timer. Thus, CTF 135 is in the forwarding path of UE 105 for atransient period of time so CTF 135 may detect the downlink trafficdestined for UE 105 and initiate the appropriate paging procedures.

Graphical representation 300B illustrates a fabric mobility event inwhich UE 105 exits idle mode (e.g., comes back online after the pagingprocedures). The forwarding state of CTF 135 in the forwarding path forUE 105 is subsequently removed when UE 105 wakes up and goes intoconnected mode. Once the state is reversed, CTF 135 is no longer in thepath for the downlink traffic destined for UE 105. Instead, theforwarding state reflects the RLOC of switch 155 (as illustrated bydashed line 310), or any other suitable network node currently servingas the RLOC for UE 105. As shown, UE 105 is now attached to switch 155.Thus, CTF 135 may be brought into the user plane path when needed, andmay be removed from the user plane path when not needed.

In one alternative example to method 200, CTF 135 may provideinstructions to cause CTF 135 to be notified when border node 165obtains the downlink packet from DN 120 by providing instructions toprovide a control plane message (instead of the downlink packet itself)to CTF 135. CTF 135 may obtain an indication that UE 105 has entered anidle mode, and, in response, provide the instructions to provide thecontrol plane message to CTF 135. Providing the instructions may includeproviding MS 145 with an update indicating that UE 105 is reachable viathe RLOC of border node 165 (e.g., associating the EID of UE 105 withthe RLOC of border node 165) and that if there is a packet for UE 105,border node 165 is to notify CTF 135 with a control plane message.

When border node 165 obtains a new downlink packet, border node 165determines that the downlink packet is destined for UE 105, and that theassociated RLOC is the RLOC of border node 165 itself. Border node 165also determines that border node 165 is to send the control planemessage to CTF 135 (e.g., over Hypertext Transfer Protocol (HTTP) or anyother suitable protocol). Border node 165 may additionally drop thedownlink packet, or buffer the downlink packet for delivery when theRLOC changes from the RLOC of border node 165. CTF 135 obtains thecontrol plane message indicating that border node 165 obtained thedownlink packet, and, in response, activates the paging process. UE 105wakes up from idle mode and registers with switch 155, and MS 145 andborder node 165 have states reflecting UE 105 as reachable via the RLOCcorresponding to switch 155 (or to a network node associated withanother AP, such as AP 125(2) or AP 125(3)). For example, MS 145 mayprovide a map update to border node 165. Border node 165 may provide thebuffered downlink packet, and any further downlink packets destined forUE 105, to UE 105.

In another alternative example to method 200, CTF 135 may provideinstructions to cause CTF 135 to be notified when border node 165obtains the downlink packet from DN 120 by providing instructions toprovide a control plane message (instead of the downlink packet itself)to MS 145. CTF 135 may obtain an indication that UE 105 has entered anidle mode, and, in response, provide the instructions to provide thecontrol plane message to CTF 135. Providing the instructions may includeproviding MS 145 with an update indicating that UE 105 is reachable viathe RLOC of border node 165 (e.g., associating the EID of UE 105 withthe RLOC of border node 165) and that if there is a packet for UE 105,border node 165 is to notify MS 145 with a control plane message.

When border node 165 obtains a new downlink packet, border node 165determines that the downlink packet is destined for UE 105, and that theassociated RLOC is the RLOC of border node 165 itself. Border node 165also determines that border node 165 is to send an update to MS 145.Border node 165 may additionally buffer the downlink packet. Border node165 sends the update to MS 145 to switch the mapping of the EID of UE105 to the RLOC of CTF 135. This triggers MS 145 to send a control planemessage (e.g., a map notify message) to CTF 135. CTF 135 obtains thecontrol plane message indicating that border node 165 obtained thedownlink packet, and, in response, activates the paging process. UE 105wakes up from idle mode and registers with switch 155, and MS 145 andborder node 165 have states reflecting UE 105 as reachable via the RLOCcorresponding to switch 155 (or to a network node associated withanother AP, such as AP 125(2) or AP 125(3)). For example, MS 145 mayprovide a map update to border node 165. Border node 165 may provide thebuffered downlink packet, and any further downlink packets destined forUE 105, to UE 105.

FIGS. 3C and 3D illustrate example graphical representations 300C and300D of UE mobility from a forwarding perspective when UE 105transitions between an idle mode (e.g., RRC idle mode) and a connectedmode (e.g., RRC connected mode) according to the alternative examples tomethod 200. Graphical representation 300C illustrates a fabric mobilityevent in which UE 105 enters idle mode. Here, network fabric 115 hides(in a forwarding sense, as illustrated by dashed line 315) UE 105 behindborder node 165 when the network detects that the idle timer has expiredand the reachability state of UE 105 is unknown. To accomplish this,network fabric 115 registers border node 165 as the RLOC for UE 105 upondetecting the expiry of the idle timer. Thus, border node 165 is in theforwarding path of UE 105 for a transient period of time so border node165 may detect the downlink traffic destined for UE 105 and initiate theappropriate paging procedures.

Graphical representation 300D illustrates a fabric mobility event inwhich UE 105 exits idle mode (e.g., comes back online after the pagingprocedures). The forwarding state of border node 165 in the forwardingpath for UE 105 is subsequently removed when UE 105 wakes up and goesinto connected mode. Once the state is reversed, border node 165 is nolonger in the path for the downlink traffic destined for UE 105.Instead, the forwarding state reflects the RLOC of switch 155 (asillustrated by dashed line 320), or any other suitable network nodecurrently serving as the RLOC for UE 105. As shown, UE 105 is nowattached to switch 155. Thus, border node 165 may be brought into theuser plane path when needed, and may be removed from the user plane pathwhen not needed.

FIG. 4 illustrates a hardware block diagram of an example device 400configured to support UE paging (e.g., CTF 135). It should beappreciated that FIG. 4 provides only an illustration of one embodimentand does not imply any limitations with regard to the environments inwhich different embodiments may be implemented. Many modifications tothe depicted environment may be made.

As depicted, the device 400 includes a bus 412, which providescommunications between computer processor(s) 414, memory 416, persistentstorage 418, communications unit 420, and Input/Output (I/O)interface(s) 422. Bus 412 can be implemented with any architecturedesigned for passing data and/or control information between processors(such as microprocessors, communications and network processors, etc.),system memory, peripheral devices, and any other hardware componentswithin a system. For example, bus 412 can be implemented with one ormore buses.

Memory 416 and persistent storage 418 are computer readable storagemedia. In the depicted embodiment, memory 416 includes Random AccessMemory (RAM) 424 and cache memory 426. In general, memory 416 caninclude any suitable volatile or non-volatile computer readable storagemedia. Instructions for paging logic 170 may be stored in memory 416 orpersistent storage 418 for execution by computer processor(s) 414.

One or more programs may be stored in persistent storage 418 forexecution by one or more of the respective computer processors 414 viaone or more memories of memory 416. The persistent storage 418 may be amagnetic hard disk drive, a solid state hard drive, a semiconductorstorage device, Read-Only Memory (ROM), Erasable Programmable ROM(EPROM), Flash memory, or any other computer readable storage media thatis capable of storing program instructions or digital information.

The media used by persistent storage 418 may also be removable. Forexample, a removable hard drive may be used for persistent storage 418.Other examples include optical and magnetic disks, thumb drives, andsmart cards that are inserted into a drive for transfer onto anothercomputer readable storage medium that is also part of persistent storage418.

Communications unit 420, in these examples, provides for communicationswith other data processing systems or devices. In these examples,communications unit 420 includes one or more network interface cards.Communications unit 420 may provide communications through the use ofeither or both physical and wireless communications links.

I/O interface(s) 422 allows for input and output of data with otherdevices that may be connected to device 400. For example, I/Ointerface(s) 422 may provide a connection to external devices 428 suchas a keyboard, keypad, a touch screen, and/or some other suitable inputdevice. External devices 428 can also include portable computer readablestorage media such as database systems, thumb drives, portable opticalor magnetic disks, and memory cards.

Software and data used to practice embodiments can be stored on suchportable computer readable storage media and can be loaded ontopersistent storage 418 via I/O interface(s) 422. I/O interface(s) 422may also connect to a display 430. Display 430 provides a mechanism todisplay data to a user and may be, for example, a computer monitor.

FIG. 5 is a flowchart of an example method 500 for supporting UE paging.In this example, a control plane entity of a network fabric (e.g., CTF135) performs method 500. At 510, the control plane entity obtains anindication that a UE connected to the network fabric has entered an idlemode. At 520, in response to obtaining the indication that the UE hasentered the idle mode, the control plane entity sets a routing locatorcorresponding to the UE to cause the control plane entity to trigger apaging request toward the UE to prompt the UE to transition from theidle mode when a first network node of the network fabric obtains adownlink packet destined for the user equipment. At 530, the controlplane entity obtains a notification that the first network node hasobtained the downlink packet. At 540, in response to obtaining thenotification that the first network node has obtained the downlinkpacket, the control plane entity initiates the paging request toward theUE. At 550, upon obtaining an indication that the UE has transitionedfrom the idle mode, the control plane entity updates the routing locatorcorresponding to the UE to cause the first network node to transmitfurther downlink packets destined for the UE toward a second networknode of the network fabric configured to handle traffic on behalf of theUE.

Techniques described herein may enable an interworking between elementsof the 3GPP control plane and the fabric user plane based on LISParchitecture to support 3GPP UE paging procedures in the fabric userplane. In one example, the network may, for a transient period of time,bring a CTF in the forwarding path for downlink traffic destined for UE105 to indicate when the downlink traffic has been received. In otherexamples, the CTF may receive one or more control plane messages toindicate when the downlink traffic has been received. Once the CTFdetermines that the downlink traffic has been received, the CTF mayinitiate paging procedures, and may subsequently reverse the state whenthe UE wakes up and goes into connected mode. Furthermore, this approachneed not require any changes on the UE stack.

The programs described herein are identified based upon the applicationfor which they are implemented in a specific embodiment. However, itshould be appreciated that any particular program nomenclature herein isused merely for convenience, and thus the embodiments should not belimited to use solely in any specific application identified and/orimplied by such nomenclature.

Data relating to operations described herein may be stored within anyconventional or other data structures (e.g., files, arrays, lists,stacks, queues, records, etc.) and may be stored in any desired storageunit (e.g., database, data or other repositories, queue, etc.). The datatransmitted between entities may include any desired format andarrangement, and may include any quantity of any types of fields of anysize to store the data. The definition and data model for any datasetsmay indicate the overall structure in any desired fashion (e.g.,computer-related languages, graphical representation, listing, etc.).

The present embodiments may employ any number of any type of userinterface (e.g., Graphical User Interface (GUI), command-line, prompt,etc.) for obtaining or providing information, where the interface mayinclude any information arranged in any fashion. The interface mayinclude any number of any types of input or actuation mechanisms (e.g.,buttons, icons, fields, boxes, links, etc.) disposed at any locations toenter/display information and initiate desired actions via any suitableinput devices (e.g., mouse, keyboard, etc.). The interface screens mayinclude any suitable actuators (e.g., links, tabs, etc.) to navigatebetween the screens in any fashion.

The environment of the present embodiments may include any number ofcomputer or other processing systems (e.g., client or end-user systems,server systems, etc.) and databases or other repositories arranged inany desired fashion, where the present embodiments may be applied to anydesired type of computing environment (e.g., cloud computing,client-server, network computing, mainframe, stand-alone systems, etc.).The computer or other processing systems employed by the presentembodiments may be implemented by any number of any personal or othertype of computer or processing system (e.g., desktop, laptop, PersonalDigital Assistant (PDA), mobile devices, etc.), and may include anycommercially available operating system and any combination ofcommercially available and custom software (e.g., machine learningsoftware, etc.). These systems may include any types of monitors andinput devices (e.g., keyboard, mouse, voice recognition, etc.) to enterand/or view information.

It is to be understood that the software of the present embodiments maybe implemented in any desired computer language and could be developedby one of ordinary skill in the computer arts based on the functionaldescriptions contained in the specification and flow charts illustratedin the drawings. Further, any references herein of software performingvarious functions generally refer to computer systems or processorsperforming those functions under software control. The computer systemsof the present embodiments may alternatively be implemented by any typeof hardware and/or other processing circuitry.

The various functions of the computer or other processing systems may bedistributed in any manner among any number of software and/or hardwaremodules or units, processing or computer systems and/or circuitry, wherethe computer or processing systems may be disposed locally or remotelyof each other and communicate via any suitable communications medium(e.g., Local Area Network (LAN), Wide Area Network (WAN), Intranet,Internet, hardwire, modem connection, wireless, etc.). For example, thefunctions of the present embodiments may be distributed in any manneramong the various end-user/client and server systems, and/or any otherintermediary processing devices. The software and/or algorithmsdescribed above and illustrated in the flow charts may be modified inany manner that accomplishes the functions described herein. Inaddition, the functions in the flow charts or description may beperformed in any order that accomplishes a desired operation.

The software of the present embodiments may be available on anon-transitory computer useable medium (e.g., magnetic or opticalmediums, magneto-optic mediums, floppy diskettes, Compact Disc ROM(CD-ROM), Digital Versatile Disk (DVD), memory devices, etc.) of astationary or portable program product apparatus or device for use withstand-alone systems or systems connected by a network or othercommunications medium.

The communication network may be implemented by any number of any typeof communications network (e.g., LAN, WAN, Internet, Intranet, VirtualPrivate Network (VPN), etc.). The computer or other processing systemsof the present embodiments may include any conventional or othercommunications devices to communicate over the network via anyconventional or other protocols. The computer or other processingsystems may utilize any type of connection (e.g., wired, wireless, etc.)for access to the network. Local communication media may be implementedby any suitable communication media (e.g., LAN, hardwire, wireless link,Intranet, etc.).

Each of the elements described herein may couple to and/or interact withone another through interfaces and/or through any other suitableconnection (wired or wireless) that provides a viable pathway forcommunications. Interconnections, interfaces, and variations thereofdiscussed herein may be utilized to provide connections among elementsin a system and/or may be utilized to provide communications,interactions, operations, etc. among elements that may be directly orindirectly connected in the system. Any combination of interfaces can beprovided for elements described herein in order to facilitate operationsas discussed for various embodiments described herein.

The system may employ any number of any conventional or other databases,data stores or storage structures (e.g., files, databases, datastructures, data or other repositories, etc.) to store information. Thedatabase system may be implemented by any number of any conventional orother databases, data stores or storage structures to store information.The database system may be included within or coupled to the serverand/or client systems. The database systems and/or storage structuresmay be remote from or local to the computer or other processing systems,and may store any desired data.

The embodiments presented may be in various forms, such as a system, amethod, and/or a computer program product at any possible technicaldetail level of integration. The computer program product may include acomputer readable storage medium (or media) having computer readableprogram instructions thereon for causing a processor to carry outaspects presented herein.

The computer readable storage medium can be a tangible device that canretain and store instructions for use by an instruction executiondevice. The computer readable storage medium may be, for example, but isnot limited to, an electronic storage device, a magnetic storage device,an optical storage device, an electromagnetic storage device, asemiconductor storage device, or any suitable combination of theforegoing. A non-exhaustive list of more specific examples of thecomputer readable storage medium includes the following: a portablecomputer diskette, a hard disk, a RAM, a ROM, EPROM, Flash memory, aStatic RAM (SRAM), a portable CD-ROM, a DVD, a memory stick, a floppydisk, a mechanically encoded device, and any suitable combination of theforegoing. A computer readable storage medium, as used herein, is not tobe construed as being transitory signals per se, such as radio waves orother freely propagating electromagnetic waves, electromagnetic wavespropagating through a waveguide or other transmission media (e.g., lightpulses passing through a fiber-optic cable), or electrical signalstransmitted through a wire.

Computer readable program instructions described herein can bedownloaded to respective computing/processing devices from a computerreadable storage medium or to an external computer or external storagedevice via a network, for example, the Internet, a LAN, a WAN, and/or awireless network. The network may comprise copper transmission cables,optical transmission fibers, wireless transmission, routers, firewalls,switches, gateway computers and/or edge servers. A network adapter cardor network interface in each computing/processing device receivescomputer readable program instructions from the network and forwards thecomputer readable program instructions for storage in a computerreadable storage medium within the respective computing/processingdevice.

Computer readable program instructions for carrying out operations ofthe present embodiments may be assembler instructions,Instruction-Set-Architecture (ISA) instructions, machine instructions,machine dependent instructions, microcode, firmware instructions,state-setting data, configuration data for integrated circuitry, oreither source code or object code written in any combination of one ormore programming languages, including an object oriented programminglanguage such as Python, C++, or the like, and procedural programminglanguages, such as the “C” programming language or similar programminglanguages. The computer readable program instructions may executeentirely on the user's computer, partly on the user's computer, as astand-alone software package, partly on the user's computer and partlyon a remote computer or entirely on the remote computer or server. Inthe latter scenario, the remote computer may be connected to the user'scomputer through any type of network, including a LAN or a WAN, or theconnection may be made to an external computer (for example, through theInternet using an Internet Service Provider). In some embodiments,electronic circuitry including, for example, programmable logiccircuitry, Field-Programmable Gate Arrays (FPGA), or Programmable LogicArrays (PLA) may execute the computer readable program instructions byutilizing state information of the computer readable programinstructions to personalize the electronic circuitry, in order toperform aspects presented herein.

Aspects of the present embodiments are described herein with referenceto flowchart illustrations and/or block diagrams of methods, apparatus(systems), and computer program products according to the embodiments.It will be understood that each block of the flowchart illustrationsand/or block diagrams, and combinations of blocks in the flowchartillustrations and/or block diagrams, can be implemented by computerreadable program instructions.

These computer readable program instructions may be provided to aprocessor of a general purpose computer, special purpose computer, orother programmable data processing apparatus to produce a machine, suchthat the instructions, which execute via the processor of the computeror other programmable data processing apparatus, create means forimplementing the functions/acts specified in the flowchart and/or blockdiagram block or blocks. These computer readable program instructionsmay also be stored in a computer readable storage medium that can directa computer, a programmable data processing apparatus, and/or otherdevices to function in a particular manner, such that the computerreadable storage medium having instructions stored therein comprises anarticle of manufacture including instructions which implement aspects ofthe function/act specified in the flowchart and/or block diagram blockor blocks.

The computer readable program instructions may also be loaded onto acomputer, other programmable data processing apparatus, or other deviceto cause a series of operational steps to be performed on the computer,other programmable apparatus or other device to produce a computerimplemented process, such that the instructions which execute on thecomputer, other programmable apparatus, or other device implement thefunctions/acts specified in the flowchart and/or block diagram block orblocks.

The flowchart and block diagrams in the figures illustrate thearchitecture, functionality, and operation of possible implementationsof systems, methods, and computer program products according to variousembodiments. In this regard, each block in the flowchart or blockdiagrams may represent a module, segment, or portion of instructions,which comprises one or more executable instructions for implementing thespecified logical function(s). In some alternative implementations, thefunctions noted in the blocks may occur out of the order noted in thefigures. For example, two blocks shown in succession may, in fact, beexecuted substantially concurrently, or the blocks may sometimes beexecuted in the reverse order, depending upon the functionalityinvolved. It will also be noted that each block of the block diagramsand/or flowchart illustration, and combinations of blocks in the blockdiagrams and/or flowchart illustration, can be implemented by specialpurpose hardware-based systems that perform the specified functions oracts or carry out combinations of special purpose hardware and computerinstructions.

The descriptions of the various embodiments have been presented forpurposes of illustration, but are not intended to be exhaustive orlimited to the embodiments disclosed. Many modifications and variationswill be apparent to those of ordinary skill in the art without departingfrom the scope and spirit of the described embodiments. The terminologyused herein was chosen to best explain the principles of theembodiments, the practical application or technical improvement overtechnologies found in the marketplace, or to enable others of ordinaryskill in the art to understand the embodiments disclosed herein.

In one form, a method is provided. The method comprises: at a controlplane entity of a network fabric: obtaining an indication that a userequipment connected to the network fabric has entered an idle mode; inresponse to obtaining the indication that the user equipment has enteredthe idle mode, setting a routing locator corresponding to the userequipment to cause the control plane entity to trigger a paging requesttoward the user equipment to prompt the user equipment to transitionfrom the idle mode when a first network node of the network fabricobtains a downlink packet destined for the user equipment; obtaining anotification that the first network node has obtained the downlinkpacket; in response to obtaining the notification that the first networknode has obtained the downlink packet, initiating the paging requesttoward the user equipment; and upon obtaining an indication that theuser equipment has transitioned from the idle mode, updating the routinglocator corresponding to the user equipment to cause the first networknode to transmit further downlink packets destined for the userequipment toward a second network node of the network fabric configuredto handle traffic on behalf of the user equipment.

In one example, setting the routing locator corresponding to the userequipment includes setting the routing locator to a routing locator ofthe control plane entity. In a further example, obtaining thenotification that the first network node has obtained the downlinkpacket includes obtaining the downlink packet. In another furtherexample, the method further comprises: at the control plane entity:buffering the downlink packet; and in response to updating the routinglocator, providing the downlink packet to the user equipment.

In one example, setting the routing locator corresponding to the userequipment includes setting the routing locator to a routing locator ofthe first network node. In a further example, the first network nodebuffers the downlink packet and provides the downlink packet to the userequipment in response to the control plane entity updating the routinglocator. In another further example, obtaining the notification that thefirst network node has obtained the downlink packet includes obtaining acontrol plane message from the first network node. In still anotherfurther example, obtaining the notification that the first network nodehas obtained the downlink packet includes obtaining a control planemessage from another control plane entity. In one example, the othercontrol plane entity is a Locator Identity Separation Protocol (LISP)Map-Server.

In another form, an apparatus is provided. The apparatus comprises: anetwork interface configured to obtain or provide network communicationsin a network fabric; and one or more processors coupled to the networkinterface, wherein the one or more processors are configured to: obtainan indication that a user equipment connected to the network fabric hasentered an idle mode; in response to obtaining the indication that theuser equipment has entered the idle mode, set a routing locatorcorresponding to the user equipment to cause the apparatus to trigger apaging request toward the user equipment to prompt the user equipment totransition from the idle mode when a first network node of the networkfabric obtains a downlink packet destined for the user equipment; obtaina notification that the first network node has obtained the downlinkpacket; in response to obtaining the notification that the first networknode has obtained the downlink packet, initiate the paging requesttoward the user equipment; and upon obtaining an indication that theuser equipment has transitioned from the idle mode, update the routinglocator corresponding to the user equipment to cause the first networknode to transmit further downlink packets destined for the userequipment toward a second network node of the network fabric configuredto handle traffic on behalf of the user equipment.

In another form, one or more non-transitory computer readable storagemedia are provided. The non-transitory computer readable storage mediaare encoded with processing instructions that, when executed by aprocessor of a control plane entity of a network fabric, cause theprocessor to: obtain an indication that a user equipment connected tothe network fabric has entered an idle mode; in response to obtainingthe indication that the user equipment has entered the idle mode, set arouting locator corresponding to the user equipment to cause the controlplane entity to trigger a paging request toward the user equipment toprompt the user equipment to transition from the idle mode when a firstnetwork node of the network fabric obtains a downlink packet destinedfor the user equipment; obtain a notification that the first networknode has obtained the downlink packet; in response to obtaining thenotification that the first network node has obtained the downlinkpacket, initiate the paging request toward the user equipment; and uponobtaining an indication that the user equipment has transitioned fromthe idle mode, update the routing locator corresponding to the userequipment to cause the first network node to transmit further downlinkpackets destined for the user equipment toward a second network node ofthe network fabric configured to handle traffic on behalf of the userequipment.

The above description is intended by way of example only. Although thetechniques are illustrated and described herein as embodied in one ormore specific examples, it is nevertheless not intended to be limited tothe details shown, since various modifications and structural changesmay be made within the scope and range of equivalents of the claims.

What is claimed is:
 1. A method comprising: at a control plane entity ofa network fabric: obtaining an indication that a user equipmentconnected to the network fabric has entered an idle mode; in response toobtaining the indication that the user equipment has entered the idlemode, setting a routing locator corresponding to the user equipment tocause the control plane entity to trigger a paging request toward theuser equipment to prompt the user equipment to transition from the idlemode when a first network node of the network fabric obtains a downlinkpacket destined for the user equipment; obtaining a notification thatthe first network node has obtained the downlink packet; in response toobtaining the notification that the first network node has obtained thedownlink packet, initiating the paging request toward the userequipment; and upon obtaining an indication that the user equipment hastransitioned from the idle mode, updating the routing locatorcorresponding to the user equipment to cause the first network node totransmit further downlink packets destined for the user equipment towarda second network node of the network fabric configured to handle trafficon behalf of the user equipment.
 2. The method of claim 1, wherein:setting the routing locator corresponding to the user equipment includessetting the routing locator to a routing locator of the control planeentity.
 3. The method of claim 2, wherein: obtaining the notificationthat the first network node has obtained the downlink packet includesobtaining the downlink packet.
 4. The method of claim 2, furthercomprising: at the control plane entity: buffering the downlink packet;and in response to updating the routing locator, providing the downlinkpacket to the user equipment.
 5. The method of claim 1, wherein: settingthe routing locator corresponding to the user equipment includes settingthe routing locator to a routing locator of the first network node. 6.The method of claim 5, wherein the first network node buffers thedownlink packet and provides the downlink packet to the user equipmentin response to the control plane entity updating the routing locator. 7.The method of claim 5, wherein: obtaining the notification that thefirst network node has obtained the downlink packet includes obtaining acontrol plane message from the first network node.
 8. The method ofclaim 5, wherein: obtaining the notification that the first network nodehas obtained the downlink packet includes obtaining a control planemessage from another control plane entity.
 9. The method of claim 8,wherein the other control plane entity is a Locator Identity SeparationProtocol (LISP) Map-Server.
 10. An apparatus comprising: a networkinterface configured to obtain or provide network communications in anetwork fabric; and one or more processors coupled to the networkinterface, wherein the one or more processors are configured to: obtainan indication that a user equipment connected to the network fabric hasentered an idle mode; in response to obtaining the indication that theuser equipment has entered the idle mode, set a routing locatorcorresponding to the user equipment to cause the apparatus to trigger apaging request toward the user equipment to prompt the user equipment totransition from the idle mode when a first network node of the networkfabric obtains a downlink packet destined for the user equipment; obtaina notification that the first network node has obtained the downlinkpacket; in response to obtaining the notification that the first networknode has obtained the downlink packet, initiate the paging requesttoward the user equipment; and upon obtaining an indication that theuser equipment has transitioned from the idle mode, update the routinglocator corresponding to the user equipment to cause the first networknode to transmit further downlink packets destined for the userequipment toward a second network node of the network fabric configuredto handle traffic on behalf of the user equipment.
 11. The apparatus ofclaim 10, wherein the one or more processors are further configured to:set the routing locator to a routing locator of the apparatus; obtainthe downlink packet; buffer the downlink packet; and in response toupdating the routing locator, provide the downlink packet to the userequipment.
 12. The apparatus of claim 10, wherein the one or moreprocessors are further configured to: set the routing locator to arouting locator of the first network node, wherein the first networknode buffers the downlink packet and provides the downlink packet to theuser equipment.
 13. The apparatus of claim 12, wherein the one or moreprocessors are further configured to: obtain a control plane messagefrom the first network node.
 14. The apparatus of claim 12, wherein theone or more processors are further configured to: obtain a control planemessage from another control plane entity.
 15. The apparatus of claim14, wherein the control plane entity is a Locator Identity SeparationProtocol (LISP) Map-Server.
 16. One or more non-transitory computerreadable storage media encoded with processing instructions that, whenexecuted by a processor of a control plane entity of a network fabric,cause the processor to: obtain an indication that a user equipmentconnected to the network fabric has entered an idle mode; in response toobtaining the indication that the user equipment has entered the idlemode, set a routing locator corresponding to the user equipment to causethe control plane entity to trigger a paging request toward the userequipment to prompt the user equipment to transition from the idle modewhen a first network node of the network fabric obtains a downlinkpacket destined for the user equipment; obtain a notification that thefirst network node has obtained the downlink packet; in response toobtaining the notification that the first network node has obtained thedownlink packet, initiate the paging request toward the user equipment;and upon obtaining an indication that the user equipment hastransitioned from the idle mode, update the routing locatorcorresponding to the user equipment to cause the first network node totransmit further downlink packets destined for the user equipment towarda second network node of the network fabric configured to handle trafficon behalf of the user equipment.
 17. The one or more non-transitorycomputer readable storage media of claim 16, wherein the processinginstructions further cause the processor to: set the routing locator toa routing locator of the control plane entity; obtain the downlinkpacket; buffer the downlink packet; and in response to updating therouting locator, provide the downlink packet to the user equipment. 18.The one or more non-transitory computer readable storage media of claim16, wherein the processing instructions further cause the processor to:set the routing locator to a routing locator of the first network node,wherein the first network node buffers the downlink packet and providesthe downlink packet to the user equipment.
 19. The one or morenon-transitory computer readable storage media of claim 16, wherein theprocessing instructions further cause the processor to: obtain a controlplane message from the first network node.
 20. The one or morenon-transitory computer readable storage media of claim 16, wherein theprocessing instructions further cause the processor to: obtain a controlplane message from a Locator Identity Separation Protocol (LISP)Map-Server.